PIA09881: Ring-Moon Connections

This Cassini view features several interesting attributes that show how
moons help shape the rings of Saturn.

The embedded moon Daphnis (7 kilometers, or 4.3 miles across) is seen in
its narrow gap at lower right. The tiny moon is accompanied by its
entourage of edge waves, visible as ripples in the gap’s edges.

Right of center, the much broader Encke Gap displays its own edge waves,
caused by Pan (26 kilometers, or 16 miles across at its widest point).
Also seen are several faint ringlets that inhabit the gap along with Pan.

Just outside, or leftward, of the Encke Gap is a dark, rippling moire
pattern, which occurs when two separate patterns in the rings are
superposed on each other but are oriented at different angles to each
other. In this case, the moire pattern is created by interference between
wakes caused by a recent passage of Pan and a spiral density wave created
by the moon Prometheus. (See PIA08824 for a
closer view of a spiral density wave.)

This view looks toward the unilluminated side of the rings from about 4
degrees above the ringplane. The narrow F ring arcs through the scene from
lower right toward left.

The image was taken in visible light with the Cassini spacecraft
narrow-angle camera on March 4, 2008. The view was obtained at a distance
of approximately 1.3 million kilometers (800,000 miles) from Saturn. Image
scale is 8 kilometers (5 miles) per pixel in the radial, or outward from
Saturn, direction.

The Cassini-Huygens mission is a cooperative project of NASA, the European
Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory,
a division of the California Institute of Technology in Pasadena, manages
the mission for NASA’s Science Mission Directorate, Washington, D.C. The
Cassini orbiter and its two onboard cameras were designed, developed and
assembled at JPL. The imaging operations center is based at the Space
Science Institute in Boulder, Colo.